Beamforming of Lamb Waves Using 2D Arrays: A Comparative Study

Abstract

Structural health monitoring (SHM) of plate-like structures can be performed using 2D array of transducers. An optimal array topology as well as an efficient beamforming scheme becomes essential when designing a beamformer based on 2D arrays. In this paper we consider both aspects of the beamforming design process. We outline a consistent methodology including theoretical, numerical and experimental investigation of a diversity of 2D array topologies in application to the beamforming of LWs. We compare a number of symmetrical 2D topologies forming circular, star-like and square patterns. In the second part we propose and analyze multi-static beamformers with sparse transmission apertures and compare their performance with classical beamformer based on the mono-static phased array approach.